Piezoelectrically driven telephone type-ringer

ABSTRACT

A piezoelectrically driven telephone-type ringer comprises a pair of gongs, a clapper rod including a clapper mounted on a free end thereof between the gongs and a piezoelectric driver device coupled to the opposite end of the clapper rod, to provide vibratory motion thereto for engagement with the gongs. The piezoelectric device is preferably of a type similar to that shown in U.S. Pat. No. 3,676,722, including a circular bender element operable in an oil can mode; i.e. the center point thereof being displaceable alternately in opposite directions substantially perpendicular to the plane of the element. A clapper rod support structure couples the piezoelectric device to the clapper rod. The support structure is fabricated of spring metal including a planar member coupled to the piezoelectric device for movement in a direction longitudinally of the plane of the member. The clapper rod is attached to a surface of the planar member, substantially perpendicular thereto, so that energization of the element with alternately poled current causes the member to move in a back and forth motion, thereby moving the clapper rod in opposite directions into alternate engagement with the gongs. The displacement of the piezoelectric element is small, but is magnified by the provision of a relatively stiff clapper rod to produce a high system resonant frequency, greater than the frequency of alternating current conventionally applied to a telephone-type ringer. The clapper fits loosely on the clapper rod to minimize its affect on the system resonant frequency.

United States Patent 1 Sehafft 14 1 Oct. 1, 1974 PIEZOELECTRICALLY DRIVEN TELEPHONE TYPE-RINGER Hugo Willy Schafft, Desplaines, 111.

[73] Assignee: Motorla Inc., Franklin Park, 111.

[22] Filed: Feb. 8, 1973 [21] Appl. No.: 330,835

Related US. Application Data [63] Continuationin-part of Ser. No. 292,594, Sept. 27,

[75] Inventor:

Primary Examiner-4. D. Miller Assistant ExaminerMarl O. Budd Attorney, Agent, or Firm-Vincent J. Rauner; Ronald J. LaPorte 1 ABSTRACT A piezoelectrically driven telephone-type ringer comprises a pair of gongs, a clapper rod including a clapper mounted on a free end thereof between the gongs and a piezoelectric driver device coupled to the opposite end of the clapper rod, to provide vibratory motion thereto for engagement with the gongs. The piezoelectric device is preferably of a type similar to that shown in US. Pat. No. 3,676,722, including a circular bender element operable in an oil can mode; i.e. thecenter point thereof being displaceable alternately in opposite directions substantially perpendicular to the plane of the element. A clapper rod support structure couples the piezoelectric device to the clapper rod. The support structure is fabricated of spring metal including a planar member coupled to the piezoelectric device for movement in a direction longitudinally of the plane of the member. The clapper rod is attached to a surface of the planar member, substantially perpendicular thereto, so that energization of the element with alternately poled current causes the member to move in a back and forth motion, thereby moving the clapper rod in opposite directions into alternate engagement with the gongs. The displacement of the piezoelectric element is small, but is magnified by the provision of a relatively stiff clapper rod to produce a high system resonant frequency, greater than the frequency of alternating current conventionally applied to a telephone-type ringer. The clapper fits loosely on the clapper rod to minimize its affect on the system resonant frequency.

12 Claims, 11 Drawing Figures PIIEZOELECTRICALLY DRIVEN TELEPHONE TYPE-RINGER BACKGROUND This invention relates generally to telephone ringer assemblies and more particularly to ringer assemblies including a piezoelectric device which provides the driving force for the clapper portion thereof.

Telephone ringer assemblies which use rectangular bimorph piezoelectric bender devices for driving the bell clapper are known in the art. The bimorph device of the last-mentioned type of ringer assembly is connected at one end thereof, directly to the clapper which is held between a pair of chimes or gongs and upon energization of the piezoelectric device with alternating current, the device bends sequentially in opposite directions to drive the clapper into contacting engagement with the gongs to produce the ringing sound.

While being workable, the above mentioned type of ringer assembly suffers from several disadvantages, thoe being that the displacement required of the bimorph device is often too great and the force produced thereby is relatively small in comparison. Also, the natural resonance frequency of the ringer assembly or system is quite low, thus limiting the frequency range of operation of the device.

SUMMARY Accordingly, it is an object of the present invention to provide a new and improved piezoelectric telephone ringer assembly which overcomes the disadvantages of prior art piezoelectric ringing assemblies'described.

It is another object of the present invention to provide a telephone ringer assembly of the above described type which is operable over a wide range of frequencies and utilizes a piezoelectric driver device which has high energy conversion.

It is still another object of the present invention to provide a piezoelectric ringer assembly of the above described type which is relatively simple in construction and has a relatively low fabrication cost.

Briefly, the piezoelectric telephone ringer assembly according to the invention comprises a bell clapper support rod of a highly rigid material, such as, for example, a graphite fiber rod, alumina ceramic or beryl lium tube or the like. One end of the rod is connected to a support formed of spring metal. A circular piezoelectric driver device is provided having a convex cross-section formed by a first dish-shaped element of nickel or the like material and a second dish-shaped element of piezoelectric material having interposed therebetween a corrugated brass, low modulus member, the corrugations of which diminish in size as they approach the outer edge of the elements whereat the latter are bonded together. A thin mica sheet is provided between the brass corrugations and the nickel element. The piezoelectric driver device described is of the monomorph type; i.e. using only one piezoelectric element, but can be a bimorph if desired. An example of such a driver device is shown and described in U.S. Pat. No. 3,676,722, issued July I I, 1972, and assigned to the same assignee as the instant invention.

Application of an alternately poled current to the piezoelectric element of the driver device provides movement of the latter in an oil can mode; i.e. the center point of the device is displaced inwardly and outwardly substantially perpendicular to the plane of the element. The device has a relatively small movement or displacement, but produces high force.

A leg of the spring metal support holding the clapper or lever rod is connected at the center of the nickel element of the device. The leg is connected at the opposite end to a second leg forming an L-shaped support longitudinally thereof. The stiff clapper rod extends perpendicularly to the plane of the first-mentioned support leg. Thus, upon energization of the driver device, the first-mentioned leg moves in a back and forth motion and the second support leg bends in a hinge-like fashion to move the clapper rod in a vibratory motion so that the free end of the rod engages a pair of gongs placed on opposite sides thereof.

The clapper is held loosely on the end of the rod and therefore is movable independently of the movement of the rod.

The resonant frequency of the system or assembly is relatively high and as such is well above the frequency at which a telephone ringer device is conventionally required to operate. In a typical example, the system resonant frequency is approximately 1150 Hz with the device being operated conventionally from between 20-80 Hz.

DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a perspective view of one embodiment of a ringer assembly according to the invention;

FIG. 2 is an enlarged perspective view of the piezoelectric driver device and associated bell clapper support structure of the ringer assembly of FIG. 1;

FIG. 3 is an enlarged cross-sectional view of the piezoelectric driver device employed in the ringer assem bly of FIG. ll;

FIG. 4 is an end view of the bell clapper and support rod of the ringer assembly of FIG. 1;

FIGS. 5, 6 and 7 are enlarged, side, sectional views of the bell clapper support structure of the ringer assembly embodiment of FIG. 1 according to the invention, illustrating the movement thereof upon operation of the piezoelectric driver device;

FIG. 8 is a perspective view of another embodiment of a ringer assembly according to the invention; and

FIGS. 9-11 are enlarged, side sectional views of the bell clapper support structure of the ringer assembly embodiment of FIG. 8 according to the invention, illustrating the movement thereof upon operation of the piezoelectric driver device.

DETAILED DESCRIPTION Referring now to the drawing in greater detail, there is shown in FIG. l a ringer assembly 10 according to the invention. The ringer assembly includes a base plate 12 upon which is mounted, at one end thereof, in spaced relation, a pair of gongs or bells 14, 16. At the opposite end of the plate 12 there is mounted a piezoelectric driver device 18 and support structure 20 therefor. A clapper rod 22 extends from a second sup port structure 44 coupled to the piezoelectric driver device, to a position between gongs 14., 16. A clapper 24 is mounted at the end 58 of the rod 22 for striking the gongs upon application-of a suitable alternating current to the piezoelectric driver device 18. A washer shown between clapper 24a and end 58a of rod 22a, maintains the clapper 24a on the last-mentioned support rod. The gongs 14, 16 are conventional telephone type gongs or bells found in telephone equipment commonly in use.

The piezoelectric device 18 is a circular bender, similar to the type shown in U.S. Pat. No. 3,676,722, issued July I l, 1972 and assigned to the same assignee as the instant invention. Referring to FIG. 3 of the drawing, the bender device shown is of a monomorph type; i.e. having one piezoelectric element, but could be a bimorph if desired; i.e. having a pair of piezoelectric elements. The particular embodiment shown, includes a circular, flexible, dish-shaped metallic member 26, preferably of nickel, including a plurality of support legs such as 28, extending therefrom.

A thin sheet of insulative material 30, such as mica or the like, is bonded to the inner surface 32 of the member 28. Attached to the mica layer is a dish-shaped piezoelectric ceramic element 34. The element is bowed slightly in a direction opposite from the nickel member in the direction of extension of legs 28, to accommodate a center, corrugated vane member 36 of electrically conductive material such as brass or the like. The corrugations of the vane member, as can be seen, are greater in size at the center of the device and gradually diminish in size as they approach the edge or perimeter thereof. The dish-shaped elements of the driver device 18 are bonded together peripherally.

Application of an alternating or equivalent current from a suitable source, such as 28 (FIG. 3) connected as shown, causes the bender device to function in an oil can mode; i.e. the central area is displaced inwardly and outwardly. The displacement of the dish-shaped elements is relatively small, in the neighborhood of two degrees for elements having diameters of approximately 1% inches.

The piezoelectric driver device 18 is mounted on the base portion 41 ofa U-shaped metal bracket 40, which is mounted at a first leg 42 on the base plate 12 of the ringer assembly. Support legs 28 of the driver device extend perpendicular to the base portion 41 and are attached thereto.

A second U-shaped member 44, preferably of spring metal construction, is provided for supporting the clapper rod 22 used for driving the clapper 24 into alternate engagement with gongs 14, 16. One leg 46 of the clapper rod support member is supported between the legs 40, 42 of the first U-shaped member and a second leg 48 of the support member extends substantially perpendicular to the nickel dish element and is attached at end 50 to the central area 52 of the element. An intermediate leg 47 is formed integrally with legs 46, 48 and extends between the free end of leg 48 and leg 46.

One end 56 of the cylindrically shaped clapper rod 22 is attached to surface 54 of leg 48 of the support member 44. The opposite end 58 of the rod extends between gongs l4, l6 and carries the clapper or striking member 60 thereon. The clapper 60 is constructed of a metallic material and is washer-shaped, having a central opening 62 of a diameter slightly larger than the diameter of the clapper rod so the former is free to move independently with respect to the rod.

The clapper rod is constructed of a rigid material such as graphite fiber, alumina ceramic, beryllium, silicon carbide or the like material. The latter materials impart a high stiffness to the clapper rod which enhances the operation of the ringer assembly and aids in maintaining the system resonant frequency relatively high.

The construction of the ringer assembly as described, transforms a low displacement or movement at the driver device into a relatively large displacement at the clapper end of rod 22.

In operation, application of alternating or an equivalent current to the piezoelectric device 18 causes the latter to be displaced as described heretofore; i.e. in an oil can mode. Referring to FIGS. 5-7, in response to the application of a first polarity driving current, the piezoelectric device is bowed in a first direction (FIG. 6) to in turn drive the leg 48 of the support structure in a direction parallel to the plane thereof, and substantially perpendicular to the plane of the elements of the device. Movement of the leg 48 is somewhat restrained by support leg 47, causing the leg 48 to bow slightly as shown in FIG. 6. Leg 47 likewise is bent in a hinge-like manner at its points of interconnection, 51, 53 with legs 46 and 48, respectively, of the support structure. The clapper rod 22 is thus moved in a first direction toward a first one of the ringer gongs. Reversing the polarity of the driving current causes the piezoelectric device to be displaced in an opposite direction, to bend the legs 47, 48 as shown in FIG. 7, thereby causing the clapper rod to be moved in a direction opposite the first described direction toward the other ringer gong. Continued application of an alternating current produces a vibratory movement of the clapper rod 22. The movement of the end 56 of the clapper rod is magnified at end 58 thereof to drive clapper 60, coupled thereto, into alternate striking engagement with gongs 14, 16, to produce the ringing sound. The clapper being loosely coupled to the rod 22 moves relatively freely and thus does not enter into the natural resonance frequency of the ringer assembly.

The system or natural resonance frequency of the ringer assembly is relatively high, well above the range of frequencies at which ringer assemblies are commonly operated in a telephone arrangement. The latter is due to the stiffness of rod 22 and the construction of support structure 44 as described, which transform the small displacement or movement of the piezoelectric driver device 18 into greater movement between gongs l4, 16. Thus, the instant ringer assembly has the advantage of being operable over a greater range of frequencies than piezoelectric ringer assemblies now available.

Referring now to FIG. 8 of the drawing, there is shown therein another embodiment of the telephone ringer assembly according to the invention.

The embodiment 70 is similar to the ringer assembly 10 of FIG. 1 including a base plate upon which is mounted a pair of gongs or bells 14a, 16a. A piezoelectric driver device like that of the assembly 10 is also used to drive a clapper rod 22a in a vibratory mode for striking gongs 14a, 16a. The clapper rod 22a likewise includes a loosely coupled clapper 24a mounted on the free end 58a thereof, between gongs 14a, 16a, for striking the latter. A washer shown between clapper 24a and end 58a of rod 22a maintains the clapper 240 on the last-mentioned support rod.

The piezoelectric driver device 18a is also mounted on a U-shaped metal bracket 200, which itself is mounted at a first leg 42a on base plate 12a at a predetermined distance from the gongs 14a, 16a.

A second U-shaped member 44a of spring metal construction is also provided for supporting the clapper rod 220. Just as in the case of the support structure 44, one leg 46a of the support structure 44a is fixedly supported between legs 40a and 42a of the first described U-shaped support member 200. A second leg 48a of the U-shaped support member 44a extends substantially perpendicular to the nickel dish element 26a of the driver device 18a and is attached at end 50a thereof to the central area 52a of the element. An intermediate leg or base of the U-shaped structure 47a is formed integrally with legs 46a, 48a and extends therebetween.

In the embodiment 70 of the ringer assembly, the end 72 of the clapper rod 22a passes through points 74, 76 whereat apertures are provided in legs 46a, 46a, respectively, of the support structure 44a. As will become apparent when the operation 'of the ringer assembly 70 is described hereinafter, it is necessary only to fix the location of the free end of clapper rod 22a on leg 46a of the support structure, and thus would be essential to pass the free end of the rod through the leg. Instead, the free end of the rod 22a could merely be attached pivotally to surface 78 of the leg 46a at the location of aperture 76. Extending the end of the clapper rod through leg 46a is, however, simpler.

The passage of the end of the clapper rod 22a through legs 48a, 46a, provides a more rigid support for the clapper-rod than does the arrangement of FIG. I and eliminates substantially the bowing or flexing of leg 48a of the support structure which is evident in the case of the first described embodiment.

In operation, application of an alternately poled current to the piezoelectric device 18a causes the latter to be displaced in an oil can mode. As can be seen in FIGS. 9-11, in response to a first polarity driving current, the piezoelectric element 260 is bowed in a first direction (FIG. to drive leg 48a of the support structure in a direction parallel to the plane of the leg (see arrow) and substantially perpendicular to the plane of the element 26a of the driver device. In this case, as in the case of the embodiment of FIG. I, the bend areas Sla, 53a of the support structure between legs 47a and legs 46a and 480, respectively, serve as hinges to permit the leg 47a to be moved pivotally to the right about hinge Slla. The clapper rod 22a which is inserted through both legs 48a and 46a of the support structure is likewise pivoted to the right about point 76 whereat the clapper rod passes through the lastmentioned leg. The movement of leg 48a to the right, as seen in FIG. 10, moves the point of attachment 74 of rod 22a to leg 48a to the right which leg 46a remains substantially stationary, to produce the pivotal movement of the clapper rod about point 76.

Reversing the polarity of the current causes the piezoelectric driver device to be displaced in the opposite direction, bowing element 26a as shown in FIG. ill, to drive leg Ma of the support structure in a direction parallel to the plane of the leg (see arrow) to the left as seen in the drawing, thereby pivoting clapper rod 22a about point 76 to the left also, for engagement of clapper 24a with gong 14a. It should be noted, that the leg 67a and clapper rod portion 78 extending between legs 46a, 48a, are maintained substantially parallel to each other during operation of the device. Thus, if desired,

the clapper rod 22a could be attached directly to leg 48a in parallel relation therewith to provide similar pivotal movement of the clapper rod.

The system or natural resonance frequency of the ringer assembly of FIG. 8 is likewise relatively high, well above the frequencies at which ringer assemblies are operated in telephone arrangements. This is provided because of the stiffness of rod 22a and the rigid support thereof in support structure 44a. The relatively small displacement or movement of the element 26a of the piezoelectric driver device 18a is magnified by the clapper rod 22a. In the embodiment of FIG. 8, the magnification of movement is directly related to the length of the clapper rod between point 74, 76 with respect to the total length thereof.

The piezoelectric ringer assembly according to the invention is a highly reliable, relatively low cost device which is operable over virtually the entire range of frequencies, i.e. 20-80 Hz, commonly used by telephone companies for ringing current.

As mentioned heretofore, the preferred embodiment of the piezoelectric circular bender driver device 18 is shown as a monomorph, having only a single ceramic piezoelectric element 34. If desired, however, a bimorph device having a pair of ceramic piezoelectric elements may be used as the driver for the ringing assembly according to the invention. In the latter case, the second piezoelectric element would be substituted for the dish-shaped nickel member.

In addition to the use of the piezoelectric driver device and associated rod and support structure as a telephone ringer assembly, the arrangement also may have use as a low power motor, in watches, clocks, pumps, tape drives and the like devices.

While a particular embodiment of the invention has been shown and described, it should be understood that the invention is not limited thereto since many modifications may be made. It is therefore contemplated to cover by the present application any and all such modifications as fall within the true spirit and scope of the appended claims.

I claim:

ll. Telephone-type ringer apparatus operable from a source of alternating current having a predetermined frequency; said apparatus including in combination: gong means, clapper means including a substantially rigid support rod mounted with one end adjacent said gong means for striking engagement therewith; piezoelectric driver means including at least one circular piezoelectric element operable in an oil can mode for predetermined displacement at the center thereof in a back and forth motion and for providing a resultant, relatively high force upon energization by application of said alternating current; and support rod support structure means for translating and magnifying the predetermined displacement of said element'into a greater displacement of said one end of said support rod adjacent said gong means while maintaining a relatively high force output thereat, said support rod structure including a first planar member extending substantially perpendicular to the surface of said piezoelectric ele ment and attached atone end thereto, and a second planar member hingedly connected at one end to the free end of said first planar member and extending substantially perpendicular thereto, the opposite end of said second planar member being held pivotally at a fixed location, said first planar member being flexible and movable in a back and forth motion along the extent of the plane thereof in response to the energization of said piezoelectric element, said support rod being attached near the end thereof opposite said end adjacent said gong means, substantially perpendicular to the surface of said first planar member for vibratory movement in response to the movement of said member upon energization of said piezoelectric element so that said one end of said support rod strikes said gong means, the system resonance frequency of said ringer apparatus being substantially greater than the frequency of said alternating current.

2. Telephone-type ringer apparatus as claimed in claim 1 wherein said one piezoelectric element has a diameter of a predetermined length and wherein said piezoelectric driver means further includes a second circular element having a diameter similar to that of said piezoelectric element, said elements being joined together near the edges thereof and a third circular element having raised portions interposed between said piezoelectric and second elements, the raised portions of said third element being higher at the center thereof and diminishing in height toward the edge, causing said outer elements to be convex in opposite directions.

3. Telephone-type ringer apparatus as claimed in claim 2 wherein said third circular element comprises a corrugated vane member having a plurality of corrugations of varying size, the larger corrugations being located centrally of said element and the size of said corrugation gradually diminishing toward the periphery of said element, the apices of said corrugations being coupled to said first and second elements, respectively.

4. Telephone-type ringer apparatus as claimed in claim 1 wherein said clapper means includes a gong striking member mounted on said support rod at the end thereof adjacent said gong means, said striking member having an aperture therethrough, larger in dimension than the outer dimension of said support rod and receiving said support rod therein, said striking member being freely movable with respect to said support rod and being movable thereby for engagement with said gong means in response to the operation of said piezoelectric driver means.

5. Telephone-type ringer apparatus as claimed in claim 4 wherein said gong means includes a pair of gongs mounted in spaced relation with the end of said support rod including said striking member positioned therebetween for sequential engagement thereof in accordance with the operation of said piezoelectric driver means by said source of alternating current.

6. Telephone-type ringer apparatus operable from a source of alternately applied opposite polarity current; said apparatus including in combination: gong means; clapper means including a substantially rigid support rod mounted with one end adjacent said gong means for striking engagement therewith; piezoelectric drive means including a piezoelectric element movable in an oil can mode for predetermined displacement thereof and for providing a resultant, relatively high force upon energization by application of said current; a clapper rod support structure for translating and magnifying the predetermined displacement of said element into a predeterminedly larger displacement of said one end of said support rod while maintaining a relatively high force output, said support structure including a U- shaped member having first and second legs and a base member adjoining said legs at said first ends thereof, a first leg of said support structure being held rigidly at a predetermined location and the free end of said second leg being coupled to said piezoelectric element, said support rod being attached to said second leg near the opposite end of said rod, and extending outwardly therefrom at substantially right angles with respect thereto, said second leg being driven in a back and forth motion along the plane thereof in response to the energization of said piezoelectric element, said support member bending at the areas of interconnection be tween said base portion and said legs in response thereto, to drive said support rod in a vibratory motion so that said one end is driven into striking engagement with said gong means, the system resonant frequency of said ringer apparatus being substantially greater than the frequency of said alternating current.

7. Telephone-type ringer apparatus as claimed in claim 6 wherein said piezoelectric driver means comprises a circular driver having at least one convex piezoelectric element and a second element convex in the opposite direction attached to said piezoelectric element at the periphery.

8. Telephone-type ringer apparatus as claimed in claim 7 wherein said support rod is of a highly rigid material and has a predetermined thickness, and wherein said support rod includes at the free end thereof a gong striking member, said gong striking member including an aperture therein larger in dimension than the outside dimension of said support rod, the last-mentioned rod received in said aperture to mount said striking member loosely thereon for independent movement with respect thereto.

9. Telephone-type ringer apparatus as claimed in claim 6 wherein the free end of said support rod passes through said first and second legs of said support structure, whereby upon energization of said piezoelectric drive means, said rod is pivoted about the end portion thereof passing through said rigidly held first leg of said support structure.

10. Apparatus for driving an elongated member in a vibratory mode by the application to said apparatus of an alternately poled current, said apparatus including in combination: piezoelectric driver means including at least one piezoelectric element operable in an oil can mode for predetermined displacement thereof in a back and forth motion and for providing a resultant, relatively high force, upon energization by application of said current; and a support structure for said member coupled to said piezoelectric driver means for translating and magnifying the predetermined displacement of said element while maintaining a relatively high force output, said support structure including a first planar member extending generally perpendicular to the surface of said piezoelectric element and attached at one end thereto, and a second planar member hingedly connected at one end to the free end of said first planar member and extending substantially perpendicular thereto, the opposite end of said second planar member being held pivotally at a fixed location, said first planar member being movable in a back and forth motion along the extent of the plane thereof in response to the energization of said piezoelectric element, said member being attached near one end thereof, substantially perpendicular to the surface of said first planar member and in parallel relation to said second planar member for vibratory movement in reand wherein said one end of said elongated member is attached to said support structure in parallel relation to said base portion for parallel movement therewith about the free end of said member in response to the energization of said piezoelectric element.

12. Apparatus as claimed in claim 11 wherein said one end of said elongated member passes through said first leg of said U-shaped structure and is attached pivotally to said second leg of said support structure. 

1. Telephone-type ringer apparatus operable from a source of alternating current having a predetermined frequency; said apparatus including in combination: gong means, clapper means including a substantially rigid support rod mounted with one end adjacent said gong means for striking engagement therewith; piezoelectric driver means including at least one circular piezoelectric element operable in an oil can mode for predetermined displacement at the center thereof in a back and forth motion and for providing a resultant, relatively high force upon energization by application of said alternating current; and support rod support structure means for translating and magnifying the predetermined displacement of said element into a greater displacement of said one end of said support rod adjacent said gong means while maintaining a relatively high force output thereat, said support rod structure including a first planar member extending substantially perpendicular to the surface of said piezoelectric element and attached at one end thereto, and a second planar member hingedly connected at one end to the free end of said first planar member and extending substantially perpendicular thereto, the opposite end of said second planar member being held pivotally at a fixed location, said first planar member being flexible and movable in a back and forth motion along the extent of the plane thereof in response to the energization of said piezoelectric element, said support rod being attached near the end thereof opposite said end adjacent said gong means, substantially perpendicular to the surface of said first planar member for vibratory movement in response to the movement of said member upon energization of said piezoelectric element so that said one end of said support rod strikes said gong means, the system resonance frequency of said ringer apparatus being substantially greater than the frequency of said alternating current.
 2. Telephone-type ringer apparatus as claimed in claim 1 wherein said one piezoelectric element has a diameter of a predetermined length and wherein said piezoelectric driver means further includes a secoNd circular element having a diameter similar to that of said piezoelectric element, said elements being joined together near the edges thereof and a third circular element having raised portions interposed between said piezoelectric and second elements, the raised portions of said third element being higher at the center thereof and diminishing in height toward the edge, causing said outer elements to be convex in opposite directions.
 3. Telephone-type ringer apparatus as claimed in claim 2 wherein said third circular element comprises a corrugated vane member having a plurality of corrugations of varying size, the larger corrugations being located centrally of said element and the size of said corrugation gradually diminishing toward the periphery of said element, the apices of said corrugations being coupled to said first and second elements, respectively.
 4. Telephone-type ringer apparatus as claimed in claim 1 wherein said clapper means includes a gong striking member mounted on said support rod at the end thereof adjacent said gong means, said striking member having an aperture therethrough, larger in dimension than the outer dimension of said support rod and receiving said support rod therein, said striking member being freely movable with respect to said support rod and being movable thereby for engagement with said gong means in response to the operation of said piezoelectric driver means.
 5. Telephone-type ringer apparatus as claimed in claim 4 wherein said gong means includes a pair of gongs mounted in spaced relation with the end of said support rod including said striking member positioned therebetween for sequential engagement thereof in accordance with the operation of said piezoelectric driver means by said source of alternating current.
 6. Telephone-type ringer apparatus operable from a source of alternately applied opposite polarity current; said apparatus including in combination: gong means; clapper means including a substantially rigid support rod mounted with one end adjacent said gong means for striking engagement therewith; piezoelectric drive means including a piezoelectric element movable in an oil can mode for predetermined displacement thereof and for providing a resultant, relatively high force upon energization by application of said current; a clapper rod support structure for translating and magnifying the predetermined displacement of said element into a predeterminedly larger displacement of said one end of said support rod while maintaining a relatively high force output, said support structure including a U-shaped member having first and second legs and a base member adjoining said legs at said first ends thereof, a first leg of said support structure being held rigidly at a predetermined location and the free end of said second leg being coupled to said piezoelectric element, said support rod being attached to said second leg near the opposite end of said rod, and extending outwardly therefrom at substantially right angles with respect thereto, said second leg being driven in a back and forth motion along the plane thereof in response to the energization of said piezoelectric element, said support member bending at the areas of interconnection between said base portion and said legs in response thereto, to drive said support rod in a vibratory motion so that said one end is driven into striking engagement with said gong means, the system resonant frequency of said ringer apparatus being substantially greater than the frequency of said alternating current.
 7. Telephone-type ringer apparatus as claimed in claim 6 wherein said piezoelectric driver means comprises a circular driver having at least one convex piezoelectric element and a second element convex in the opposite direction attached to said piezoelectric element at the periphery.
 8. Telephone-type ringer apparatus as claimed in claim 7 wherein said support rod is of a highly rigid material and has a predetermined thickness, and wherein said support rod inclUdes at the free end thereof a gong striking member, said gong striking member including an aperture therein larger in dimension than the outside dimension of said support rod, the last-mentioned rod received in said aperture to mount said striking member loosely thereon for independent movement with respect thereto.
 9. Telephone-type ringer apparatus as claimed in claim 6 wherein the free end of said support rod passes through said first and second legs of said support structure, whereby upon energization of said piezoelectric drive means, said rod is pivoted about the end portion thereof passing through said rigidly held first leg of said support structure.
 10. Apparatus for driving an elongated member in a vibratory mode by the application to said apparatus of an alternately poled current, said apparatus including in combination: piezoelectric driver means including at least one piezoelectric element operable in an oil can mode for predetermined displacement thereof in a back and forth motion and for providing a resultant, relatively high force, upon energization by application of said current; and a support structure for said member coupled to said piezoelectric driver means for translating and magnifying the predetermined displacement of said element while maintaining a relatively high force output, said support structure including a first planar member extending generally perpendicular to the surface of said piezoelectric element and attached at one end thereto, and a second planar member hingedly connected at one end to the free end of said first planar member and extending substantially perpendicular thereto, the opposite end of said second planar member being held pivotally at a fixed location, said first planar member being movable in a back and forth motion along the extent of the plane thereof in response to the energization of said piezoelectric element, said member being attached near one end thereof, substantially perpendicular to the surface of said first planar member and in parallel relation to said second planar member for vibratory movement in response to the movement of said first planar member upon energization of said piezoelectric element.
 11. Apparatus as claimed in claim 10 wherein said support structure is U-shaped with said first planar member being one of the legs of the U and the second planar member being the base of the U, and including a second leg extending substantially parallel to said first leg, the legs of said U-shaped support structure being hingedly connected to the base portion thereof and said second leg of the support structure being held fixed, and wherein said one end of said elongated member is attached to said support structure in parallel relation to said base portion for parallel movement therewith about the free end of said member in response to the energization of said piezoelectric element.
 12. Apparatus as claimed in claim 11 wherein said one end of said elongated member passes through said first leg of said U-shaped structure and is attached pivotally to said second leg of said support structure. 